Snow Blindness

Steer clear of this painful yet preventable condition.

Snow blindness, a form of photokeratitis, is a painful eye condition caused by exposure to ultraviolet (UV) rays reflected from ice and snow, particularly at high elevation. Severe cold and dryness can also cause the condition.

It is usually not noticed until sometime after the damage is done, just like a sunburn. Snow blindness symptoms can be very alarming and unpleasant, including blurry vision, swelling, and watery eyes.

But you don't have to experience the pain and damage that snow blindness causes. In fact, for centuries humans have found clever ways to protect themselves, and with today's technology it's easier than ever to stay safe. Sunglasses or goggles that block 99 percent and higher of UV rays and protect from dry, freezing wind can help prevent snow blindness.

Inuit Innovation

Even before today's innovative eyewear, people have found ways to stay safe on cold, sunny winter days. Alaskan Inuits carved snow goggles from caribou antlers to help prevent UV exposure. The goggles featured a narrow slit that limited brightness but allowed for a full horizontal field of vision, blocking UV rays reflecting vertically off the ice and snow.

Doug Swingley and the 2004 Iditarod

A famous case of snow blindness occurred during the 2004 Iditarod sled dog race. Leading his team through a particularly notorious section of the 1,000-mile trail during extreme cold and wind, racer Doug Swingley removed his goggles for a quick look ahead. In a matter of minutes, his vision became extremely blurry. When he wasn’t sure if he should continue, Swingley called Griffith Steiner, MD, a corneal specialist based in Anchorage. “Based on the severity of his symptoms and the danger of proceeding, I advised him that it was not safe to continue,” said Dr. Steiner. “This was not an easy decision, as Doug was a four-time champion.” He ultimately left the race for treatment in Anchorage, and his eyes fully recovered.

Swingley likely had a freezing injury to his corneas exacerbated by severe dryness from exposure to the cold wind as well as low humidity. A recent laser vision correction — which can make dry eye symptoms more likely — also exacerbated the situation.

Under those extreme conditions and his set of circumstances, it's difficult to say if Swingley could have avoided snow blindness. However, for most outdoor enthusiasts, a safe day in the winter sun is almost assured with a good pair of sunglasses or ski goggles.